Vertical impact crusher

Abstract

A vertical impact crusher comprises a rotor supported for rotation at a high rotating speed about a vertical axis, and having discharge gates through which a material fed into the rotor is discharged for crushing. Each discharge gate is provided in one side thereof with a pair of hard chips provided respectively with cemented carbide chips and stacked one over the other so as to be replaced with each other. Each hard chip has upper and lower portions projecting in the direction of rotation of the rotor, and each cemented carbide has upper and lower portions projecitng in the direction of rotation of the rotor. The hard chips provided respectively with the cemented carbide chips are replaced with each other after the working surfaces of the hard chips and the cemented carbide chips have been abraded to some extent. The surfaces of the new hard chips and the new cemented carbide chips are formed so as to guide the flow of the material toward the upper and lower portions of the stack of the hard chips and the cemented carbide chips so that the recesses formed between the upper and lower portions of the hard chips and the cemented carbide chips are abraded more intensively than the middle portion of the stack of the hard chips and the cemented carbide chips in the initial stage of use and so that the middle portion of the stack is abraded more intensively than the upper and lower portions of the stack after the mutual replacement of the hard chips together with the cemented carbide chips.

What is claimed is: 
     
       1. A vertical impact crusher comprising: a rotor supported for high speed rotation in a direction of rotation about a vertical axis, said rotor having at least one discharge gate through which a material fed to the rotor may be discharged;   a pair of hard chips at each said at least one discharge gate, said chips of each pair of chips being positioned adjacent one another in the vertical direction; and   a pair of cemented carbide chips stacked on each said pair of hard chips, the upper and lower chips of each said pair of cemented carbide chips abutting one another in the direction of the vertical axis, each of said cemented carbide chips having upper and lower projecting portions which project in the direction of rotation to define a recess therebetween, wherein the upper projecting portion of the lower chip abuts the lower projecting portion of the upper chip and there are two of said recesses at each said at least one discharge gate,   whereby the life of said cemented carbide chips may be improved if the positions of said chips are reversed when the cemented carbide chips are partially abraded.   
     
     
       2. The vertical impact crusher of claim 1, including a plurality of said discharge gates.